PLASMA PROCESSING APPARATUS AND OPERATIONAL METHOD THEREOF

• US 20170372878A1
• Filed: 08/15/2017
• Published: 12/28/2017
• Est. Priority Date: 07/18/2013
• Status: Active Grant

• Current Assignee: Hitachi High-Tech Company Limited (Hitachi, Ltd.)
• Original Assignee: Hitachi High-Technologies Corporation (Hitachi, Ltd.)
• Inventors: TOGAMI, Masahito, USUI, Tatehito, HIROTA, Kosa, INOUE, Satomi, NAKAMOTO, Shigeru
• Granted Patent: US 11,424,110 B2
• Time in Patent Office: Days
• CPC Class Codes: H01J 2237/0266 electromagnetic
• CPC Class Codes: H01J 2237/2445 Photon detectors for X-rays, light, e.g. photomultipliers
• CPC Class Codes: H01J 2237/3341 Reactive etching
• CPC Class Codes: H01J 37/32458 Vessel
• CPC Class Codes: H01J 37/32908 Utilities
• CPC Class Codes: H01J 37/32963 End-point detection
• CPC Class Codes: H01J 37/32972 Spectral analysis
• CPC Class Codes: H01J 37/3299 Feedback systems

Abstract

A plasma processing apparatus includes: a detector configured to detect a change in an intensity of light emission from plasma formed inside a processing chamber; and a unit configured to adjust conditions for forming the plasma or processing a wafer arranged inside the processing chamber using an output from the detector, wherein the detector detects a signal of the intensity of light emission at plural time instants before an arbitrary time instant during processing, and wherein the adjusting unit removes the component of a temporal change of a long cycle of the intensity of light emission from this detected signal and detects the component of a short temporal change of the intensity of light emission, and adjusts the conditions for forming the plasma or processing a wafer arranged inside the processing chamber based on the short temporal change of the detected intensity of light emission.

Claims

1-5. -5. (canceled)

6. A method for operating a plasma processing apparatus comprising:

a processing chamber arranged inside a vacuum vessel;

a detector configured to detect a change in an intensity of light emission from plasma formed inside the processing chamber; and

a unit configured to adjust conditions for forming the plasma or processing a wafer arranged inside the processing chamber using an output from the detector, the method comprising the steps of;

detecting, by the detector, a signal of the intensity of light emission at a plurality of time instants before an arbitrary time instant during processing;

removing the component of a temporal change of a long cycle of the intensity of light emission from the detected signal and detecting a component of a short temporal change of the intensity of light emission; and

adjusting the conditions for forming the plasma or processing a wafer arranged inside the processing chamber based on the short temporal change of the detected intensity of light emission.

7. The method for operating a plasma processing apparatus according to claim 6, further comprising the step of detecting the component of a temporal change of a long cycle of the intensity of light emission from the signal of the intensity of light emission at a plurality of time instants before an arbitrary time instant during processing, using an infinite impulse response filter.

8. The method for operating a plasma processing apparatus according to claim 6, further comprising the steps of:

reducing noise using an infinite impulse response filter from the signal of the intensity of light emission at a plurality of time instants before an arbitrary time instant during processing; and

after the step above, removing the component of a temporal change of a long cycle of the intensity of light emission from the detected signal and detecting the component of a short temporal change of the intensity of light emission.

9. The method for operating a plasma processing apparatus according to claim 7, wherein the infinite impulse response filter is a Kalman filter.

10. The method for operating a plasma processing apparatus according to claim 6, further comprising the steps of:

reducing noise from the signal of the intensity of light emission at a plurality of time instants before an arbitrary time instant during processing, using a Kalman filter; and

after the step above, detecting the component of a temporal change of a long cycle of the intensity of light emission from the signal whose noise is reduced, using a Kalman filter; and

removing the component of a temporal change of a long cycle of the intensity of light emission from the signal whose noise is reduced and detecting the component of a short temporal change of the intensity of light emission.